Final answer:
The area of the cross section of the tunnel is 8π square meters and the volume of air that can be contained in the tunnel is 1920π cubic meters.
Step-by-step explanation:
To calculate the area of the cross section of the tunnel, we can use the formula for the area of a semicircle, which is A = (πr^2)/2. Since the radius of the tunnel is 4 meters, the area is A = (π*(4^2))/2 = 8π square meters.
To calculate the volume of air that can be contained in the tunnel, we can multiply the area of the cross section by the length of the tunnel. Since the length is 240 meters, the volume is 8π * 240 = 1920π cubic meters.